The invention relates to a wheel bearing for a driven rigid axle, having a drive shaft which is mounted in or on an axle body.
Elements of this invention are disclosed in DE 197 44 871 A1. A rolling bearing, for example of a multi-link axle, bears axially with its inner race against a shaft shoulder of the drive shaft while the outer race is pressed into an axle stub. The brake disk, which has a wheel-supporting surface, sits with a serrated profile on a corresponding mating profile of the drive shaft. With the aid of a central screw on the drive shaft, the brake disk is clamped against the rolling bearing and the latter is clamped against the shaft shoulder of the drive shaft. Including the thread, there are five settlement joints in this case.
If the brake disk is removed, the central fastening screw has to be undone. In the process, the inner race of the rolling bearing can be released from bearing against the shaft shoulder. After installation of, for example, a new brake disk, the central screw is tightened again.
There is the risk here of the rolling bearing being prevented, for example because of fretting corrosion, from reaching its original position on the shaft shoulder. This may lead to the joints of the connection settling, which may cause a reduction in the prestressing force.
The transverse and longitudinal forces acting on the wheel during the driving mode act directly as an alternating stress on the wheel-bearing fastening and can thus further loosen the wheel fastening.
The problem on which the present invention is based is therefore to develop a wheel bearing for a driven rigid axle, in which it is possible to remove a brake disk without releasing the wheel bearing.
This problem is solved by the features of the invention described and claimed herein. For this purpose, the wheel bearing is provided with a rolling bearing unit which comprises at least one inner race and at least one outer race, an inner race which is oriented toward the outside of the vehicle being designed with an end flange aligned in this direction and having, at least along a partial region of its length, a hub profile of a shaft-hub connection, the hub profile being connected to a complementary profile arranged on the drive shaft, having an axle body which is mounted in a rotationally fixed manner on the vehicle body, radially surrounds the drive shaft at least along a partial region of its length and forms or accommodates an outer race of the rolling bearing unit, having a wheel flange which accommodates at least one drive wheel, and having a brake disk which comprises a friction ring and a brake-disk chamber, the brake disk being releasably fastened together with the wheel flange to the end flange of the inner race.
In order to remove the brake disk, the releasable connection, with which the brake disk and the wheel flange are fastened to the inner race of the rolling bearing unit, is released. In the meantime, the rolling bearing unit can be fixed axially and/or radially. In order to change the brake disk, the latter is removed together with the wheel flange. A new brake disk is then fitted in turn together with the wheel flange and fastened releasably to the inner race of the rolling bearing unit. Only this connection has to be released and fastened again in order to change the brake disk. No additional components are released or loosened in the process. Including the thread, there are at most four settlement joints in the fastening of the releasable connection.
The torque from the drive shaft is transmitted via a form-fitting shaft-hub connection to the inner race of the rolling bearing unit. Via the end flange on the inner race of the rolling bearing unit, the torque is passed on further via the frictional flange connections between the inner race and the brake disk and between the brake disk and the wheel flange to the wheel flange and from there to the wheels. The wheel flange may also be part of the brake disk. In this case, a driving torque from the inner race is transmitted via a frictional connection to the brake disk and is passed on from there directly to the wheel flange.
A braking torque is transmitted by the brake disk to the wheel flange. If a brake disk is integrated in the wheel flange, the braking torque is passed directly from the brake disk into the wheel flange. If the brake disk and the wheel flange are separate components, the transmission of the braking torque takes place, for example, via a frictional and/or form-fitting connection between the brake disk and the wheel flange.
The brake disk can be centered during installation and can be fitted simply and securely.